source: NonGTP/Boost/boost/pointee.hpp @ 857

Revision 857, 1.9 KB checked in by igarcia, 19 years ago (diff)
RevLine 
[857]1#ifndef POINTEE_DWA200415_HPP
2# define POINTEE_DWA200415_HPP
3
4//
5// Copyright David Abrahams 2004. Use, modification and distribution is
6// subject to the Boost Software License, Version 1.0. (See accompanying
7// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
8//
9// typename pointee<P>::type provides the pointee type of P.
10//
11// For example, it is T for T* and X for shared_ptr<X>.
12//
13// http://www.boost.org/libs/iterator/doc/pointee.html
14//
15
16# include <boost/detail/is_incrementable.hpp>
17# include <boost/iterator/iterator_traits.hpp>
18# include <boost/type_traits/add_const.hpp>
19# include <boost/type_traits/remove_cv.hpp>
20# include <boost/mpl/if.hpp>
21# include <boost/mpl/eval_if.hpp>
22
23namespace boost {
24
25namespace detail
26{
27  template <class P>
28  struct smart_ptr_pointee
29  {
30      typedef typename P::element_type type;
31  };
32
33  template <class Iterator>
34  struct iterator_pointee
35  {
36      typedef typename iterator_traits<Iterator>::value_type value_type;
37     
38      struct impl
39      {
40          template <class T>
41          static char test(T const&);
42         
43          static char (& test(value_type&) )[2];
44         
45          static Iterator& x;
46      };
47     
48      BOOST_STATIC_CONSTANT(bool, is_constant = sizeof(impl::test(*impl::x)) == 1);
49     
50      typedef typename mpl::if_c<
51#  if BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x551))
52          ::boost::detail::iterator_pointee<Iterator>::is_constant
53#  else
54          is_constant
55#  endif
56        , typename add_const<value_type>::type
57        , value_type
58      >::type type;
59  };
60}
61
62template <class P>
63struct pointee
64  : mpl::eval_if<
65        detail::is_incrementable<P>
66      , detail::iterator_pointee<P>
67      , detail::smart_ptr_pointee<P>
68    >
69{
70};
71 
72} // namespace boost
73
74#endif // POINTEE_DWA200415_HPP
Note: See TracBrowser for help on using the repository browser.